We've got two big-time birthdays to celebrate, but I think we'll start with Academy Award-winner Sean Penn, who turns 51 today. Now, I've heard that Penn is a rather polarizing figure as a result of his political tendencies - I know my father isn't much of a fan - but I don't think there's any way you can deny his acting prowess. The man snagged his Oscar wins in 2004 and 2004, effectively establishing himself as one of the pre-eminent acting forces on the Hollywood scene in the 21st century. So, as I always do, I've counted down my five favorite of Penn's roles, supplying a clip for each of them. I hope you enjoy the post as you help me celebrate Sean Penn's birthday!